Multi-mode communication interface for PLC expanding machine and host machine and the appication method thereof

Abstract

A multi-type communication interface between the PLC extension computer and host computer and application method are disclosed that include: host computer and at least one extension computer, said extension computer has microprocessor, storage unit and communication interface, the connective module of the communication interface with several functions of integrated circuit is connected with the host computer or the extension computer, and setting the I / O point extension to form the connection that defined by the multi-type extension computer and communication interface framework according with the I / O point, the initialized action of host computer can read the type of extension computer and the capability by the judging module of communication interface, and the position value is output to the extension computer according to the control request, the extension computer can allow and separate the data sent by the host computer automatically according to the position value received by the communication interface, and stores the data stored in the storage element temporary.

Description

Technical field [0001] The invention relates to a multi-mode communication interface between a PLC expansion machine and a host and an application method thereof, in particular to a serial digital point expansion mode, a serial and parallel expansion mode of a special expansion machine, etc., which can be matched with a general or special expansion machine Multi-mode, multi-mode expansion machine connection, and through the connection module of the integrated circuit of the communication interface, you can set the required I / O points to expand the PLC expansion machine and the host's multi-mode connection communication interface, thereby improving the communication method and The expansion of I / O points requires separate hardware design and other issues. Background technique [0002] In the prior art, programmable logic controllers (PLC, Programmable Logic-Controller) applied to the operation control of external devices are connected to external devices or equipment through its e...

AI Technical Summary

Problems solved by technology

When the user uses the expansion unit to display the value on the multi-segment display and read the value of the scanning keyboard, the hardware of the expansion unit needs to emulate the I / O points, and at the same time, the corresponding program needs to be written on the software of the host computer, which is quite inconvenient. , in other words, both the host and extension designers must design matching hardware communication methods, resulting in a double waste of time

[0007] In addition, the above-mentioned expansion machines connected to the host are not all digital expansion machines. If the above-mentioned known communication architecture is used to connect the host and non-digital or other special expansion machines for communication and transmission, when the expansion machine is detected, the expansion The software designers on the machine side need to communicate with the software designers on the host side, but cannot do other work, resulting in work restrictions and time wastage

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